Abstract
On the basis of body weight, most flying insects have higher rates of metabolism, and hence heat production, than other animals. However, rapid rates of cooling because of small body size in most cases precludes appreciable endothermy. The body temperature of small flies in flight is probably close to ambient temperature, and that of flying butterflies and locusts is 5° to 10°C above ambient temperature. Many moths and bumblebees are insulated with scales and hair, and their metabolism during flight can cause the temperature of the flight muscles to increase 20° to 30°C above ambient temperature.